Japanese Laid-Open Patent Publication No. 2013-226621 discloses a design for a stackable case that is configured to link or couple an upper case to a lower case via interlocking latches that also serve to lock a lid of the case in a closed position. The lid for the upper case is locked in its closed position by the interlocking latches and the lid for the lower case is locked in its closed position by the upper case being stacked on and linked to the lower case. When the engagement of the latches is released, each of the upper and lower cases can be used as a separate case and each lid can be locked with its own latches. This design enables two or more of the stacked cases to be carried in a linked or joined manner by using the interlocking latches as connectors for both locking the lids in their closed state and for joining the cases to each other. The plurality of stacked, joined cases can be easily and conveniently carried with one or more electric power tools and/or its/their accessories being stored separately in a plurality of cases.